Browsing by Author "Mwiine, Frank Norbert"
Now showing 1 - 11 of 11
Results Per Page
Sort Options
Item Comparative detection of African swine fever virus by loop-mediated isothermal amplification assay and polymerase chain reaction in domestic pigs in Uganda(African Journal of Microbiology Research, 2014) Atuhaire, David Kalenzi; Afayoa, Mathias; Katiti, Dianah; Mwiine, Frank Norbert; Nanteza, Ann; Mugasa, Claire Mack; Matovu, Enock; Olaho-Mukani, William; Ojok, LonzyAfrican swine fever (ASF) is a contagious viral disease, which can cause up to 100% mortality among domestic pigs. Pig production is growing rapidly in Uganda among East African countries and is not only a source of food but also an important income for many people living in the rural areas. Field diagnosis of ASF depends only on clinical signs and has to be confirmed in the laboratory since the clinical signs are not pathognomonic. Diagnostic techniques for ASF are focused on serological tests for detection of antigen and antibody, genomic DNA detection by polymerase chain reaction (PCR), and on virus isolation and localization in clinical samples. There have been many recent reports of ASF outbreaks in Uganda yet laboratory diagnosis is limited due to the high cost and expertise required. This work reports the evaluation and application of a loop-mediated isothermal amplification (LAMP) test for detecting African swine fever virus (ASFV) DNA based on the topoisomerase II gene. Thirty (30) tissue samples obtained from suspected ASF outbreaks were collected from different regions of Uganda. The tissue samples were found to have lesions consistent with ASF. One hundred and eighty eight (188) additional blood samples were obtained from the abattoir and field surveillance. Six primers targeting the topoisomerase II gene were used. The sensitivity and specificity of LAMP and OIE recommended diagnostic PCR were compared. The LAMP assay is rapid with results obtained within 1 h (45-60 min). The sensitivity of LAMP for the detection of ASFV was 100% (95% CI: 91.78-100) while the specificity was 44% (95% CI: 36.52-51.69). The Kappa statistic for level of agreement between PCR and LAMP test in the detection of ASFV was 23.7% (95% CI: 16.42-30.91). This Kappa value indicated a fair agreement between the two assays. No cross reaction was observed with Porcine circovirus type 2virus and E. coli isolated from pigs in Uganda. This is the first study evaluating and applying the LAMP assay in the detection of ASF in domestic pigs in Uganda. The LAMP assay was found to be more sensitive than PCR. Due to its simplicity, sensitivity and specificity, the LAMP assay has the potential for use in the diagnosis and routine surveillance of ASF in Uganda.Item Comparative detection of foot-and-mouth disease virus by reverse transcription loop-mediated isothermal amplification assay and real time polymerase chain reaction in Uganda(Int J Biotechnol Food Sci, 2016) Mukasa, Hussein Kafeero; Mwiine, Frank Norbert; Atuhaire, David Kalenzi; Ochwo, Sylvester; Nanteza, AnnFoot-and-mouth disease (FMD) is a viral disease. FMD diagnosis in the field is based on clinical signs that are shared by other vesicular diseases, hence to confirm FMD a laboratory is needed. Laboratory diagnostic techniques including serology may fail to distinguish between vaccinated and new infection, virus isolation may take up to 4 days to yield results, while molecular techniques including PCR, which are accurate, sensitive, specific and rapid, are costly and require special training of the laboratory staff. These challenges limit laboratory diagnosis yet in Uganda FMD outbreaks are common since the disease is endemic. This work reports the comparative detection of Foot-and-mouth disease virus (FMDV) by reverse transcription-loop mediated isothermal amplification (RT-LAMP) and Real-Time polymerase chain reaction (rRT-PCR) in Uganda based on the 3D polymerase (3Dpol) gene. The rRT-PCR assay is considered as the gold standard. A total of 89 cattle samples that included epithelial tissues (16.9%) and oral swabs (83.1%) were collected from outbreak cases in Eastern Districts of Mbale and Budaka. These were applied to molecular assays of rRT-PCR and RT- LAMP using primers and probes targeting the 3Dpol gene. The diagnostic sensitivity and specificity of RT-LAMP as a screening test and rRT-PCR as the reference test was 94.44% (95% CI = 94.11 to 94.78%) and 98.59% (95% CI = 98.50 to 98.68%), respectively. The kappa value for diagnostic agreement between rRT-PCR and RT-LAMP was 93.0% (95% CI = 83.50 to 100%), showing a perfect agreement. In conclusion, the RT-LAMP assay had a very high sensitivity and specificity when compared to the reference test of rRT-PCR. It was also very rapid since it gave results in 45 to 60 min. Due to its simplicity, sensitivity and specificity, LAMP assay has the potential for use in routine surveillance of FMD in Uganda.Item Epidemiological Overview of African Swine Fever in Uganda (2001–2012)(Journal of Veterinary Medicine, 2013) Atuhaire, David Kalenzi; Ochwo, Sylvester; Afayoa, Mathias; Mwiine, Frank Norbert; Arinaitwe, Eugene; Ademun-Okurut, Rose Anna; Okuni, Julius Boniface; Nanteza, Ann; Ayebazibwe, Christosom; Okedi, Loyce; Olaho-Mukani, William; Ojok, LonzyAfrican swine fever (ASF) is a contagious viral disease, which can cause up to 100% mortality among domestic pigs. In Uganda there is paucity of information on the epidemiology of the disease, hence a study was carried out to elucidate the patterns of ASF outbreaks. Spatial and temporal analyses were performed with data collected monthly by the district veterinary officers (DVOs) and sent to the central administration at MAAIF from 2001 to 2012. Additionally, risk factors and the associated characteristics related to the disease were assessed based on semistructured questionnaires sent to the DVOs. A total of 388 ASF outbreaks were reported in 59 districts. Of these outbreaks, 201 (51.8%) were reported in districts adjacent to the national parks while 80 (20.6%) were adjacent to international borders. The number of reported ASF outbreaks changed over time and by geographical regions; however, no outbreak was reported in the North-Eastern region. ASF was ranked as second most important disease of pigs, and it occurred mostly during the dry season (𝑃 = 0.01). Pig movements due to trade (OR 15.5, CI 4.9–49.1) and restocking (OR 6.6, CI 2.5–17.3) were the major risk factors. ASF control strategies should focus on limiting pig movements in UgandaItem Factors That Influence Pig Production In Central Uganda - Case Study Of Nangabo Sub-County, Wakiso District(Vet World, 2012) Muhanguzi, Dennis; Lutwama, Vincent; Mwiine, Frank NorbertTo study the factors affecting pig production in Nangabo Sub-County, Wakiso District, Central Uganda. A total of 11% (1350/12783) of all households in the Nangabo Sub-County kept pigs. Theth systematic sampling technique was used to complete the list of all pig farming households. This was done by taking 10 farming household until 10% of all the farming households were sampled. Atotal of 135 farmers were interviewed with semistructured questionnaire. Questionnaire data was entered into Microsoft Excel worksheet and trans-ferred into Statistical Package for Social Scientists. Results indicated that 49.6 % of the pigs were raised in the semi-intensive system while 31%, 12% and 8% of the farmers kept pigs on intensive, tethering and free range rearing systems respectively. Farmers that raised their pigs on what is hereby referred to as semi-intensive and intensive management systems allowed their pigs up to five and two hours of open foraging respectively. Ninety eight percent of the farmers provided housing to their pigs and the commonest pig houses were local mud houses and a few of them were tree shades. Majority of farmers (85.2%) watered their pigs at least once a day. The major factors limiting pig production were; diseases and parasites mainly helminthosis and African swine fever (ASF). Others included; high costs of inputs, lack of capital, unstable availability of feed resources, inadequate advisory services and feed price fluctuation (maize bran, sow and weaner), lack of good quality breeding stock, poor and unorganized marketing, lack of enough land, high costs of veterinary medicines and inability to keep records. Additionally, lack of enough water and uncontrolled pig movement grossly limited the pig production in Wakiso district. Most Ugandans keep their pigs in periurban areas of Uganda. It was however, noted that there were important limitations for pig production in the country. To improve pig production and reduce animal protein deficit, knowledge on constraints to pig production was important to inform pig sector promotion stakeholders.Limitations to pig farming including parasites and diseases, ASF, nutritional deficiencies, high cost of inputs like building materials, drugs and veterinary services, inadequate capital and failure of farmers to access credit services,expensive feeds among others were identified and should be addressed to meet national animal protein requirements.Item Identification of Peste des Petits Ruminants Transmission Hotspots in the Karamoja Subregion of Uganda for Targeting of Eradication Interventions(Frontiers in veterinary science, 2019) Nkamwesiga, Joseph; Coffin-Schmitt, Jeanne; Ochwo, Sylvester; Mwiine, Frank Norbert; Palopoli, Annabella; Ndekezi, Christian; Isingoma, Emmanuel; Nantima, Noelina; Nsamba, Peninah; Adiba, Rogers; Hendrickx, Saskia; Mariner, Jeffrey C.This paper describes an assessment of the patterns of peste des petits ruminants virus circulation in the Karamoja subregion of Uganda conducted to identify the communities that maintain the virus and inform the development of a targeted vaccination strategy. Participatory epidemiological methods were used to develop an operational hypothesis for the patterns of PPR in Karamoja that was subsequently validated through outbreak investigation and genomics. The participatory epidemiological assessment included risk mapping with livestock owners, community animal health workers and veterinarians and indicated there were two critical foci of virus transmission on the Uganda-Kenya border. One was located in two adjacent subcounties of Kotido and Kaabong Districts in northern Karamoja and the other in Loroo subcounty of Amudat District in southern Karamoja. Participants reported that these were locations where outbreaks were usually first observed in Karamoja and subsequently spread to other areas. Following the participatory assessment, surveillance activities were implemented across the Karamoja subregion in 2018. Three outbreak were detected, investigated and sampled. Two outbreaks were located in the northern and one on the southern focus of transmission. No Outbreaks were diagnosed in Karamoja outside of these foci during 2018. Genomics indicated different clusters of viruses were associated with the northern and southern foci that were more closely related to other East African isolates than to each other. This indicates these are two separate systems of virus circulation which should be explicitly addressed in eradication as separate cross-border systems that require integrated cross-border interventions.Item Invasive Cattle Ticks in East Africa: Morphological and Molecular Confirmation of The Presence of Rhipicephalus Microplus in South‑Eastern Uganda(Parasites & Vectors, 2020) Muhanguzi, Dennis; Byaruhanga, Joseph; Amanyire, Wilson; Ndekezi, Christian; Ochwo, Sylvester; Nkamwesiga, Joseph; Mwiine, Frank Norbert; Tweyongyere, Robert; Fourie, Josephus; Madder, Maxime; Schetters, Theo; Horak, Ivan; Juleff, Nick; Jongejan, FransRhipicephalus microplus, an invasive tick species of Asian origin and the main vector of Babesia species, is considered one of the most widespread ectoparasites of livestock. The tick has spread from its native habitats on translocated livestock to large parts of the tropical world, where it has replaced some of the local populations of Rhipicephalus decoloratus ticks. Although the tick was reported in Uganda 70 years ago, it has not been found in any subsequent surveys. This study was carried out to update the national tick species distribution on livestock in Uganda as a basis for tick and tick-borne disease control, with particular reference to R. microplus.The study was carried out in Kadungulu, Serere district, south-eastern Uganda, which is dominated by small scale livestock producers. All the ticks collected from 240 cattle from six villages were identified microscopically. Five R. microplus specimens were further processed for phylogenetic analysis and species confirmation.The predominant tick species found on cattle was Rhipicephalus appendiculatus (86.9 %; n = 16,509). Other species found were Amblyomma variegatum (7.2 %; n = 1377), Rhipicephalus evertsi (2.3 %; n = 434) and R. microplus (3.6 %; n = 687). Phylogenetic analysis of the 12S rRNA, 16S rRNA and ITS2 gene sequences of R. microplus confirmed the morphological identification.It is concluded that R. microplus has replaced R. decoloratus in the sampled villages in Kadungulu sub-county, since the latter was not any longer found in this area. There is currently no livestock movement policy in force in Uganda, which could possibly limit the further spread of R. microplus ticks. Future surveys, but also retrospective surveys of museum specimens, will reveal the extent of distribution of R. microplus in Uganda and also for how long this tick has been present on livestock without being noticed.Item Measurement and Sampling Error in Mixed-Methods Research for the Control of Peste Des Petits Ruminants in the Karamoja Subregion of Northeastern Uganda: A Cautionary Tale(Preventive Veterinary Medicine, 2021) Coffin-Schmitt, Jeanne L.; Moore, Emily V.; McKune, Sarah L.; Nkamwesiga, Joseph; Isingoma, Emmanuel; Nantima, Noelina; Adiba, Rogers; Mwiine, Frank Norbert; Nsamba, Peninah; Hendrickx, Saskia; Mariner, Jeffrey C.A team of interdisciplinary researchers undertook a mixed methods, participatory epidemiology (PE) based study as part of a pilot project for localized control of Peste des petits ruminants (PPR), a small ruminant disease of high socio-economic impact. Mixed methods research combines qualitative and quantitative methods, allowing iterative comparison of results to arrive at a more comprehensive and informed outcome. In this study, the use of PE and a household survey (HHS) resulted in contradictory results. However, the mixed methods approach also facilitated the detection and the explanation of bias in the HHS, which may have gone undetected and unexplored had only one method been used. Results show that logistical constraints leading to a failure to apply key aspects of the sampling strategy led to problematic gender/ethnic composition of the HHS sample population. Additionally, while PE findings on local disease and terminology were integrated during HHS development and training, there is apparent measurement error related to enumerator bias in HHS results, possibly due to insufficient respondent understanding or a lack of analytic clarity. The extensive nature of the PE, surveillance methodologies used in the initial site assessment, and formative research for the HHS allowed for a critical analysis and interpretation of HHS results as well as reflection on the research process. The findings of this paper underscore the (1) flexibility and utility of participatory methods, (2) the importance of mixed methods research in designing health interventions, and (3) the necessity of tight integration of study design with team planning for implementation of research in environments such as Karamoja, Uganda. If all three are to be achieved not only researchers but funders must provide these space and structure beginning in the study design phase. These findings are relevant in many places, but have particular importance for international, interdisciplinary teams working from various on-and-off-site locations with traditional or indigenous knowledge systems.Item Molecular characterization of African swine fever virus in apparently healthy domestic pigs in Uganda(African Journal of Biotechnology,, 2014) Kalenzi Atuhaire, David; Ochwo, Sylvester; Afayoa, Mathias; Mwesigwa, Savannah; Mwiine, Frank Norbert; Okuni, Julius Boniface; Olaho-Mukani, William; Ojok, LonzyAfrican swine fever (ASF) is a highly lethal and economically significant disease of domestic pigs in Uganda where outbreaks regularly occur. There is neither a vaccine nor treatment available for ASF control. Twenty two African swine fever virus (ASFV) genotypes (I - XXII) have been identified based on partial sequencing of the C-terminus of the major capsid protein p72 encoded by the B646L gene. The majority of previously characterized Ugandan ASFV strains belong to genotype IX. The major aim of the current study was to determine the ASFV genotypes among asymptomatic slaughter pigs at Wambizi slaughterhouse and in some parts of the country where surveillance was done. Three discrete regions of the ASFV were analysed in the genomes of viruses detected in asymptomatic domestic pigs. The analysis was conducted by genotyping based on sequence data from three single copy ASFV genes. The E183L gene encoding the structural protein P54 and part of the gene encoding the p72 protein were used to delineate genotypes, before intra-genotypic resolution of viral relationships by analysis of tetramer amino acid repeats within the hypervariable central variable region (CVR) of the B602L gene. All the ASF viruses obtained from this study clustered with previous viruses in genotype IX based on analysis of the p72 and P54 genes. Analysis of the CVR gene grouped the viruses in three different subgroups; 13, 23 and 25. Only one genotype is circulating in Uganda among asymptomatic domestic pigs and it is the same virus causing outbreaks in the country and parts of neighbouring Kenya.Item Prevalence of African swine fever virus in apparently healthy domestic pigs in Uganda(BMC veterinary research, 2013) Atuhaire, David Kalenzi; Afayoa, Mathias; Ochwo, Sylvester; Mwesigwa, Savannah; Mwiine, Frank Norbert; Okuni, Julius Boniface; Mukani, William Olaho; Ojok, LonzyAfrican swine fever (ASF) is a contagious viral disease which can cause up to 100% mortality among domestic pigs leading to serious socio-economic impact on people’s livelihoods. ASF is endemic in Uganda and there is paucity of information on the epidemiology of the disease. The major aim of this study was to determine the seroprevalence and prevalence of African swine fever virus (ASFV) in apparently healthy slaughter pigs at Wambizi slaughterhouse in Kampala city, Uganda. We also estimated the presence of ASFV antibodies and circulating viral antigens in pigs from selected districts of Uganda during targeted surveillance. We analysed 540 and 181 blood samples collected from slaughter pigs and pigs from targeted surveillance districts respectively.The prevalence of ASFV in slaughter pigs was 52.96% (95% CI, 48.75-57.14) and 11.5% (95% CI, 9.06-14.45) by ELISA and PCR respectively. In surveillance districts, the proportion of ASFV positive pigs was 53.59% (95% CI, 46.33-60.71) and 0.55% (95% CI, 0.1-3.06) by ELISA and PCR respectively.The study has found out a high seroprevalence of ASFV antibodies in apparently healthy slaughter pigs and also a high proportion of ASFV antibody seropositive pigs in surveyed districts in Uganda indicating exposure to ASFV. However, there was a lower prevalence of ASFV infection implying that there could be low virulent strains of ASFV circulating in domestic pigs in Uganda which requires further investigation.Item Seroprevalence of contagious bovine pleuropneumonia (CBPP) in cattle from Karamoja region, North-eastern Uganda(BioMed Central Ltd, 2024-03) Tweyongyere, Robert; Nkamwesiga, Joseph; Etiang, Patrick; Mugezi, Israel; Wamala, Henry; Wasswa, Auther Tamale; Kamusiime, Maureen; Ainebyoona, Solomon; Abizera, Harriet; Mwiine, Frank Norbert; Muhanguzi, DennisBackground Contagious bovine pleuropneumonia [CBPP] is a transboundary animal disease of cattle caused by Mycoplasma mycoides subsp. mycoides [Mmm]. CBPP causes severe economic losses to livestock producers in sub-Saharan Africa mainly due to high mortality, morbidity, reduction in productivity as well as livestock trade restrictions. This study aimed at determining seroprevalence of Mmm in cattle from Karamoja region, north-eastern Uganda; data that are required to design and implement risk based CBPP control program. Methods We randomly collected blood samples from 2,300 cattle spread across Karamoja region. Serum was extracted and screened for antibodies against Mycoplasma mycoides subsp. mycoides [Mmm] using the competitive enzyme linked immunosorbent assay [cELISA]. Results A quarter [25.4%; 95% CI: 23.7-27.3] of the screened cattle [n = 2,300] were sero-positive for Mmm. Amudat and Kaabong districts recorded the lowest [12.3%] and highest [30.7%] Mmm seroprevalence respectively. Increasing age, overnight stay in cattle kraals and location [certain districts, villages, herds and sub counties] of the cattle herds, the factors that promote animal commingling, were the most significant risk factors of seroconversion with Mmm. Conclusion Results from this study indicated a higher seroprevalence of Mmm in Karamoja region cattle herds. This could be due to the increased frequency of CBPP outbreaks in recent years. To be effective, CBPP vaccination programs should target high risk herds along the international borders and other hotspot areas [e.g., parishes or sub counties] where cattle commingling is high. Keywords: Karamoja region, Uganda, Seroprevalence, CBPP, cELISA, CattleItem Spatial distribution and risk factors for foot and mouth disease virus in Uganda: Opportunities for strategic surveillance(Preventive veterinary medicine, 2019) Munsey, Anna; Mwiine, Frank Norbert; Ochwo, Sylvester; Salinas, Lauro Velazquez; Ahmed, Zaheer; Maree, Francois; Rodriguez, Luis L.; Rieder, Elizabeth; Perez, Andres; VanderWaal, KimberlyFoot-and-mouth disease virus (FMDV) has a substantial impact on cattle populations in Uganda, causing short- and long-term production losses and hampering local and international trade. Although FMDV has persisted in Uganda for at least 60 years, its epidemiology there and in other endemic settings remains poorly understood. Here, we utilized a large-scale cross-sectional study of cattle to elucidate the dynamics of FMDV spread in Uganda. Sera samples (n = 14,439) from 211 herds were analyzed for non-structural protein reactivity, an indication of past FMDV exposure. Serological results were used to determine spatial patterns, and a Bayesian multivariable logistic regression mixed model was used to identify risk factors for FMDV infection. Spatial clustering of the disease was evident, with higher risk demonstrated near international borders. Additionally, high cattle density, low annual rainfall, and pastoralism were associated with increased likelihood of FMD seropositivity. These results provide insights into the complex epidemiology of FMDV in Uganda and will help inform refined control strategies in Uganda and other FMDV-endemic settings.